Multiposition push-button switch



Mlch 25, 1969 j F, W, PFLEGER 3,435,167

. MULTIPOSITION PUSH-BUTTON SWITCH Filed Aug. s, 1967 sheet of 2 -L f/Q INVENTOR. Hennie/rz l/L/ Parri/e -yQ-JC/ 6 BY /M/a. ma

March 25, 1969 l v F, W, IDF-LEGER n 3,435,1l67

MULTIPOSITION PUSH-BUTTON SWITCH fl' Q 7 INVENTOR.

Fefpz/ae W PAZIKK/E JM/a. ma@

ATToR/VEV United States Patent O 3,435,167 MULTIPSITIN PUSH-BUTEN SWITCH Frederick W. Pfleger, 1152 Barbara Drive, Cherry Hill, NJ. 08034 Filed Aug. 3, 1967, Ser. No. 658,209 Int. Cl. H0111 19/20, 13/14, 19/14 U.S. Cl. 200--156 18 Claims ABSTRACT F THE DISCLUSURE The instant disclosure is concerned with a switch construction wherein is provided a toothed rotary member, and a pair of reciprocatory operating members on opposite sides of the axis of the rotary member each including an actuating member having an engaging portion for engagement with the rotary member to rotate the latter.

Background of the invention Prior switches of this type include rotary switches, thumbwheel switches, rotary switches operated by a push button or a rocking lever, slide switches, and the like.

In many applications o'f multiposition switches, the switches, due to the function which they perform, must be activated very frequently, As a result many improvements have been made to these type switches to simplify their operation for an operator. These improvements include changes to the contours of the thumbwheel, the addition of a single push button or the addition of rocking levers, to operate a rotary element which forms a part of this type of switch, all of which have certain disadvantages.

In many applications it is desirous to have a sealed switch in which no foreign particles can reach the electrical contacts or the operating mechanism. Due to the construction of thumbwheel switches, and rocking-lever switches, it is extremely diiicult to seal the mechanism and the electrical contacts. As a result, many applications resort to a form of push-button switch in which a button, mounted to a shaft, is used to provide the necessary motion through a seal in the front panel to actuate the rotary mechanism.

Push-button mechanisms of this type only provide for one direction of rotation of the switch. As a result, if a ten position the switch stands on an 8 position and it is desired to rest the switch to a 7 position, nine depressions of the button are required.

The addition of the push-button mechanism to the conventional type switch requires added parts and generally increases the overall size.

Switches of this rotary type as well as normal slide switches utilize etched printer circuits for one contact element. In application in which each switch position is to present a coded output, a multiplicity of boards or two-sided boards are used resulting in greatly increased cost and additional covering to seal the circuits.

In many applications it is desirable to have the switches located in a remote area, say close to the equipment which it is controlling. In this case, it may be desirable to operate the switches by pulses generated from one or many different areas. It is therefore desirable to enable this operation with as few additional parts as possible.

Summary As a result it is an object of this invention to provide a push-button rotary switch having two buttons, one for forward rotation of the switch and one for reverse rotation of the switch.

It is another object of the invention to provide a twobutton push-button switch which can be totally enclosed and sealed.

ICC

It is another object of this invention to provide a twobutton push-button switch which requires no more panel mounting space than that required for the simplest types of multiposition switches.

It is another object of this invention to provide a twobutton push-button switch with a minimum of operating parts.

It is another object of this invention to provide a twobutton push-button switch which can provide coded output or single positional outputs with a simple single-sided code plate.

It is another object of this invention to provide a twobutton push-button switch which can be remotely operated by the addition of operating solenoids only.

It is another object of this invention to provide a twobutton push-button switch in which the stroke of either button is minimal.

It is another object of this invention to provide a twobutton push-button switch in which only full strokes of the operating button will advance the switch one position. A partial stroke will not aifect the switch setting.

It is another object of the invention to provide a twobutton push-button switch which will only advance one position for each depression regardless of how the button is depressed.

It is another object of this invention to provide a twobutton push-button switch which can have a large number of unique positions while still retaining its size and simplicity.

These and other advantages will be evident from the examination of the following description and drawing.

Brief description of the drawing FIGURE l is a side elevation drawing of the switch with the cover partially removed to expose the operating components.

FIGURE 2 is a front elevation of the switch.

FIGURE 3 is a partial side elevation of the switch showing one operating button in depressed position.

FIGURE 4 is a front view of a disc commutator such as would be mounted to the wheel with individual sensing brushes mounted to the frame.

FIGURE 5 is a front view of a commutator with a set of common iingers mounted to the wheel and an irnproved commutator plate acting as the cover for the unit.

FIGURE 6 is a side elevation of the switch showing the addition of solenoids for remote operation.

FIGURE 7 is a side elevation of the switch with the cover removed which shows the use of a metallic belt as one portion of the switch member for switches requiring a large number of sensing positions.

FIGURE 8 is a partial view of a wheel with sensing iingers made from a stamping.

Description of the preferred embodiments As shown in FIGURE l, the switch comprises a housing which is, in its preferred embodiment, a plastic -mo-lding. The housing 100 is provided with a shaftlike projection 110, guide projections and 121 and control projections 1410, 141 and 142. The housing 100 is provided at the front with a face ange 102 through which is an aperture 103, a top flange 104, bottom flange 106 and a rear flange 108. The four anges are integrated with each other and with the Ihousing base 101. As a result, body 100 forms a completely enclosed case for the switch except for the cover 111 shown in part FIGURES l and 2 and other seals for openings to be described later. Rotatably mounted on shaft projection 110' is a rotary rnember or wheel 130. Wheel is provided with a peripheral flange, rim surface or drum 131 onto which is imprinted, engraved, or marked the identifying characters 132 for the position registered. A support web 133 (FIGURE 1) supports the rim and a hub 134. Hub 134 is provided with a circumferential array of r-adial teeth defining ratchet notches 135, one such notch for each position of the switch as represented by the identifying character. The support web 133 is provided with apertures for mounting contact brushes 410 of the switch for positional sensing or for mounting a code disc 401, see FIGURE 4. Positioned between the wheel 130 and the base of the housing 100 are a pair of operating members 150 and 150A, which may be substantially identical. An upper operating member 150 is mounted in the upper half of the housing 100 for rotating the wheel 130 in counterclockwise direction, see FIG- URE 1, and an identical lower operating member 150A is mounted in the lower half of the housing 100i for rotating the wheel 130 in clockwise direction. Since the two operating members 150 and 150A are identical and function identically, except for their mounting position and the direction of rotation which they impart, a detailed description of one will suffice.

As previously mentioned, it is extremely important that switches of this type occupy as little panel or mounting space as practical and still be convenient to operate. Since in most applications several of these switches are mounted adjacent one another, it is desirable to keep the spacing between indicating characters as small as possible so that visual examination of multiple switches will appear as reading a multiple-digit number. In order to accomplish this, the operating members 150 and 150A are constructed such that the maximum space required for the operating member is its own material thickness and operates in the same space as that required yfor the ratchet notches 135, as shown in FIGURES 1 and 2. Operating members 150 and 150A are provided at their respective forward ends with projections 136 4and 136A which pass through resilient seals, as at 137 in face flange 102 to the outside of the unit. These seals plus a clear window 103A in aperture 103 and the cover 111 cemented to flanges 102, 104i, 106 and 108 provide the necessary seals to form a sealed switch.

Projections 136 and 136A function as pushable members or buttons of any desirable configuration, can be secured to the projections as the pushable member. Positioned inside the body 100 are two yieldably flexible forward extensions or members 160 and 170 of operating member 150. The yieldable actuating member 160 is provided at its outer or forward end with an engaging portion, pawl or hook 161 which coacts with notches 135, a sloping or oblique surface 162 which coacts with the housing control projection 142, and an upper cam surface 163 which acts with housing control projection 141. The yieldable limiting member 170 is provided with an end face or surface 171 which coacts with the opposite sides of the notches 135 as the hook member 161 and with the corners of the same sides of notches 135 as oblique camming surface 162. Yielding members 160 and 170 are designed suc-h that the yielding of the elements will not fatigue the material from which the operating member is made. In order to accomplish this, the deflection, length, and thickness of the yield members 160 and 170` are proportioned to 4keep the bending stresses well within the yield stress of the material. Materials that function well in this type of operation include spring steel, beryllium copper, Phosphor bronze and certain plastics. The preferred material for this application is a plastic.

In order to provide proper guiding of operating member 150, a forward guide is provided by the forward projection 136 being guided as it passes through the face flange 102 and a rearward guide is provided by a slot 122 cooperating Iwith a guide projection 120 or 121; as a result the path of movement of operating member 150 is delined by the guides just described.

A rearward projection 180 is proportioned and positioned such that a coil spring 182 is guided by this rearward projection and acts to retain the operating member 150 in forward position. As a result, in nonoperated position, the operating member 150 is held in forward position by spring 182, face surface 171 of yielding member 170 is held against the forward surface of notch 135 and hook member 161 is held out of engagement lwith notch 135 by cam surface 162 resting on control projection 137. Since the two operating members 150` and 150A are identical, the face surface 171A of they yielding member 170A of operating member 150A is -held against an opposite surface of another notch 135'. Since the two notches utilized are on opposite sides of the pivot point of wheel and since opposite faces of the notches 135 are held, the wheel is held from rotating by this detenting action of the two operating members 150 and 150A. In order to assume proper registration and prevent one of springs 102 and 182A from providing more movement to its associated operating member 150 and 150A., a forward stop surface 138 and 138A (not shown) are provided on the respective operating members 150 and 150A. These stop surfaces are located by the inner surface of face flan-ge 102; as a result under nonoperated condition, the switch is held in the set detented position and is accurately located by the dimensional characteristic of the operating members.

In order to advance the switch in a selected direction, the appropriate forward projection 136 or 136A is depressed, On movement to the left, see FIG-UREl 3, the hook member 161 of yielding member 160 engages the face of a notch and on further movement to the left rotates the notch, hub and wheel. Since the operating member is movin-g to the left, the face surface 171 of yielding member 170 is also moving to the left; thus removing its locking capability from the Iwhe-el. While the wheel 130 and notches 135 are rotating, a corner of the notch 135, which the yielding member 170A was engaging, acts `with a surface of this yielding member 170A to deflect it out of engagement with this first notch and into engagement With the next notch, if the wheel and notches were fully rotated. If the operating member was not fully depressed, cam surface 162 of yielding member 160 and face surface 171 of yielding member 170 will return the wheel to its previous position. At the conclusion of a complete leftward motion of the operating member 150, the operator removes his hand from the forward projection 136 of the operating member 150 and the spring 182 returns the operating member to home position thus engaging the locking detent face 171 with the next adjacent notch 135 in the clockwise direction about the notch hub 134.

In order to insure that the hook member 161 positively engages the notch during operation, the yielding member is designed such that the free state of the hook from the pivot point of the wheel is less than the radius Of the notch hub. As a result, an engagement tension established by this dimensional difference is obtained. Since it is important that the hook member 161 engages the notch to be rotated and since the previously described engagement tension could position the hook too low for minimum operating stroke configurations, thus interfering with rotation in reverse direction, the cam surface 162 of yielding member 160 cooperates with control projection 142 to correctly position the hook member 161 for proper engagement with the notch 135. Since the cam surface has the characteristic of a very shallow Wedge, very little spring force of spring 182 is required to retain the cam 011 the control surface.

If the energy in the rotating wheel 130 is high, it would be p-ossible that the wheel would advance two or more positions during an operating-member operation. In order to prevent excess rotation, yielding member 160 is provided with an upward extending surface 163 which in the fully depressed position as shown in FIGURE 3 cooperates with lug 141. As a result Wheel 130 is prevented from moving more than one index due to the solid material stop formed by ratchet 135, hook member 151 and control projection 141 as shown in FIGURE 3.

As previously mentioned, it is sometimes desirable to operate these switches from remote means. As a result, as shown in FIGURE 6, two solenoids 701 and 702 can be mounted to the rear surface 108 of case 100.

The armatures of the solenoids 703 and 704 are pin-connected to extensions of rearward projection members 180 and 180A of operating member 150 and 150A. As aY result, electrical energy to either solenoid 701 or 702 would provide equivalent operation to the switch as depression of the operating-member forward projections 136 and 136A.

Switches of this type are used to provide electrical signaling to user equipment. This electrical signaling can take the form of digital for unique positional indications or coded information related to the position indicated. A common technique for providing this facility is the utilization of etched circuit boards. These boards as is well known in the art comprise a copper sheet clad to an insulating backing. The copper is then selectively removed from the areas in which an open contact is required.

This conventional system could be equivalent to that shown in FIGURE 4. The conductive disc 401 is selectively coated with an insulating material 430 such as a plastic to provide insulating pads between the conductive disc 401 and the other half of the electrical switch, in this case sensing brushes 410 mounted to the frame of the unit. Each of these brushes is insulated from each other and Wired independently to the output of the switch.

Since the manufacture of this type of sensing brush is very expensive, and in most cases the brushes are not Very durable, a more desirable system would be to have sensing brushes 810 as shown in FIGURE 8 capable of selectively contacting the conductor of a printed circuit board, shown in FIGURE 8, since this type of brush can be fabricated as a simple metal stamping. In order to accomplish this, most applications require that the output i board either be a two-sided board or that two sets of brushes geared together operate to give the desired output. An improved system for accomplishing the use of brushes is shown in FIGURE 8, and a single-sided printed circuit board is shown in FIGURE 5. The coded output for the binary code to the 20, 21, 22, and 23 is associated with printed circuit lines S00, 501, 502 and S03, These copper lines extend into the region in which the brushes 510 operate. These brushes are permanently fixed to the rotating member. The method of securing them is not shown since it is apparent that there are many ways for acomplishing this. Each of the lines 500, 501, 502, and 503 extend into an annular ring 520, 521, 522 and 523. As a result, the brushes 510 ride on the annular rings 520 through 523. A fifth line 505, which is electrically tied to the common connection of the switch extends to a fth annular ring 525.

To provide a selection of these iive annular rings at each speciic locating position, Nos. 0 through 9 in FIG- URE 5, an insulating material, preferably an epoxy-type resin, is selectively coated onto the annular ring. This can be accomplished by silk screening, spray, etc., which are relatively inexpensive, As shown in FIGURE 5, the brushes are located at the 0 position when the 0 character'is visible in the window 132. Since no output is required at 0, the epoxy coating 530 covers the common line 505 in all brush areas except the annular ring 525. If the rotary member indicates a 6 in the window, the brushes would have rotated to the number 6 location on FIGURE 5. In this position, the brushes 510 will make contact with the conductive surfaces of the annular rings 52S, S22 and 521. The brushes associated with annular rings 520 and 523 will not make contact since the conductor at these points has been coated with an insulating material. As a result, it can be seen that FIGURE 5 shows a very simple sensing-plate arrangement which can be extremely small in size, made with a single-sided conductor, and can be accomplished with one set of annular rings.

In many applications it may be desirable to have more than 10 or 12 sensing positions. As a result as shown in FIGURE 7 a sprocket wheel can be substituted for the rotary wheel 133 of the normal switch shown in FIG- URE 1. At the rear of the housing are two shaft projections 803 and 804. Mounted on these shaft projections are two rotatable pulleys 805 and 806. A self-recoiling spring tape 801 is mounted to the two pulleys 805 and 806 and is passed over a sprocket assembly 807. As a result, depression of the operation levers 136 and 136A provides for forward and rearward winding of this tape. In order to provide for electrical sensing of this tape 801, the inner surface 801A has deposited on it selected areas of insulating material such as previously described in relation to FIGURE 5. Sensing brushes 810 are mounted to the case cover 101 by an insulator block 811 and operate to sense the selected bare areas of the metal tape. In order to provide rigidity to the thin metal tape at the sensing point, a post 812, also mounted to the cover, is provided to produce a back bend in the tape as it passes over the post. As a result, the tape is held flat at the point of sensing by brushes 810. The front surface 801B of the tape 801 can be marked or printed with information which enables the operator, when viewing through aperture 103, to ascertain the position on which the switch is located.

As a result, it is possible to provide within a small package a switch mechanism which can easily provide for 64 or more individual selectable positions. In some applications, where the number of positions is not so great, it would also be possible to substitute the self-soiling tape with an endless tape.

As a result, from the above disclosure as read in reference to the attached drawing, we have described an improved switch which provides for simple sealing means, forward and reverse direction of rotation, a capability of a large number of selectable positions, and simplication of contact structures for such switches all contained in a small package with a minimum of parts.

Although the present invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it is understood that certain changes and modifications may be made within the spirit of the invention and scope of the appended claims.

I claim:

v1. In a multiposition switch, the combination comprising a rotary member, drive teeth on said rotary member, a pair of operating members on opposite sides of the axis of rotation of said rotary member and mounted for independent reciprocatory movement generally normal to said axis, a pair of resiliently dellectable actuating members respectively associated with said operating members for movement thereby generally tangent to opposed Iregions of said rotary member, a pair of engaging portions on respective actuating members each engageable with an adjacent tooth upon operating-member movement in one direction of said reciprocatory movement to shift said rotary member a predetermined angular distance, and detent means for said rotary member.

2. The combination according to claim 1, said detent means comprising a pair of resiliently deflectable limiting members extending from respective operating members, said limiting member of each Operating member being engageable with said teeth to prevent movement of said rotary member upon movement of the other operating member in its other direction of said reciprocatory movement. l

3. The combination according to claim 1, in combination with a pair of control projections located for camming engagement with respective actuating members to deflect the same away from said teeth upon terminal movement of the associated operating member in said other direction, to prevent obstruction to rotary-member movement by each actuating member upon movement of the other actuating member in said one direction.

4. The combination according to claim 1, in combination with a pair of camming members located for camming engagement with `respective actuating members upon movement thereof in said one direction, for limiting rotary-member movement in said one direction upon movement of said rotary member said predetermined angular distance.

5. The combination according to claim 1, in combination with stop means engageable with said operating members to limit movement thereof, and resilient means engaging said operating members to urge the latter toward said stop means.

6. The combination according to claim 5, in combination with manual actuating means carried by each of said operating members, for manual movement thereof in said one direction against the force of said resilient means.

7. The combination according to claim 5, in combination with electromechanical actuating means connected to each operating member, for remote movement thereof in said one direction against the force of said resilient means.

8. The combination according to claim 1, in combination with a drum on said rotary member adapted to be marked with indicia characterizing respective positions of rotaryemember movement.

9. The combination according to claim 1, in combination with contact areas on said rotary member, and sensing means engageable with contact areas for sensing the angular position of said rotary member.

10. The combination according to claim 1, in combination with Contact members mounted on said rotary member, and contact areas engageable with said contact members for sensing the angular position of said rotary member.

11. The combination according to claim 9, said rotary member comprising a drum carrying said contact areas.

12. The combination according to claim 1, in combination with bearing means generally parallel to and spaced from the axis of said rotary member, belt means trained about said bearing means and rotary member for rotation With the latter, contact areas on said belt means, and sensing means engageable with said contact areas for sensing the position of said belt means.

13. The combination according to claim 12, said bearing means comprising a pair of supports, and said belt means comprising a self-recoiling spring tape having its opposite end portions rotatably coiled about respective supports and its intermediate portion extending about said rotary member.

14. The combination according to claim 13, in combination with markings on said belt means characterizing the position of said belt means.

15. In an electric switch, the combination comprising a rotary member, drive teeth on said rotary member, a pair of operating members on opposite sides of the axis of rotation of said rotary member and mounted for independent reciprocatory movement generally normal to said axis, a pair of resiliently deflectable actuating members respectively associated with said operating members for movement thereby generally tangent to opposed regions of said rotary member, a pair of engaging portions on respective actuating members each engageable with an adjacent tooth upon operating-member movement in one direction of said reciprocatory movement to shift said rotary member a predetermined angular distance, detent means for said rotary member, a pair of supports in generally parallel spaced relation with said rotary member,

a self-recoiling spring tape having its opposite end por-l tions rotatably coiled about respective supports and its intermediate portion extending about said rotary member, contact areas on said tape, and sensing means engageable with said contact areas for sensing the angular position of said rotary member.

16. The combination according to claim 15, in combination with markings on said tape characterizing the angular position of said rotary member.

17. In a multiposition switch, the combination comprising a rotary member, drive teeth on said rotary member, a pair of operating members on opposite sides of the axis of -rotation of said rotary member and mounted for independent reciprocatory movement generally normal to said axis, a pair of resiliently deectable actuating members respectively associated with said operating members for movement thereby generally tangent to opposed regions of said rotary member, a pair of engaging portions on respective actuating members each engageable with an adjacent tooth upon operating-member movement in one direction of said reciprocatory movement to shift said rotary member a predetermined angular distance, detent means for said rotary member, a conductive plate selectively coated with an insulating material at each position of rotary-member movement, and a set of contacts mounted to cooperate at a contacting position with said conductive plate for sensing the selectively coated areas of said plate.

18. In an electric switch, the combination comprising a rotary member, drive teeth on said rotary member, a pair of operating members on opposite sides of the axis of rotation of said rotary member and mounted for independent reciprocatory movement generally normal to said axis, a pair of resiliently deflectable actuating members respectively associated With said operating members for movement thereby generally tangent to opposed regions of said rotary member, a pair of engaging portions on resepctive actuating members each engageable with an adjacent tooth upon operating-member movement in one direction of said reciprocatory movement to shift said rotary member a predetermined angular distance, detent means for said rotary member, a metallic tape, a pair of take-up spools, an end portion of said metallic tape on each of said take-up spools, an intermediate portion of said metallic tape extending about said rotary member,

`insulating material selectively deposited on said metallic tape forming selective electrical-contact areas, and a set of contacts mounted at a contact position for sensing the set position of said metallic tape.

References Cited UNITED STATES PATENTS 2,287,200 6/ 1942 Scott 200-46 XR 2,821,880 2/1958` Ahola 200-46 XR 2,860,199 11/1958 James et al 200e-46 3,089,923 5/ 1963 Wright.

ROBERT K. SCHAEFER, Primary Examiner.

H. BURKS, Assistant Examiner.

U.S. Cl. X.R. 200--46 

